This invention relates to drug and body treating compositions and is particularly concerned with a process for interrupting pregnancy after implantation of the fertilized ovum has taken place by administration of a p-sulfonamidoaminophenone interceptive agent.
At the present time, there are a number of available oral contraceptives containing estrogenic and progestational steroids that inhibit pregnancy by preventing ovulation if administered on an almost daily regimen. But, after fertilization and implantation of the ovum has taken place, there is presently little, short of mechanical (vacuum aspiration) or surgical abortion, that can be done to prevent delivery of viable offspring. Thus, there remains a large unmet need for a safe medication which requires infrequent or at the most only short periods of treatment to induce elimination of unwanted embryos. For the purpose of this disclosure, agents that interrupt pregnancy after implantation of the fertilized ovum are called "interceptives" as opposed to the term "contraceptives" which applies to agents that prevent pregnancy by inhibiting conception; refer to R. H. Naqvi, et al., Steroids, 18:731, 1971.
A few of the p-sulfonamidoaminophenones useful in the present invention are specifically disclosed by A. A. Larsen, et al., U.S. Pat. No. 3,341,584 to be of value as central nervous system agents. It was not recognized, however, until the present discovery that some of the p-sulfonamidoaminophenones disclosed by Larsen, et al. as well as other novel compounds of that class are effective interceptive agents.